Why Do We Need Calcium in Everyday Life?
Calcium is a silvery white metal. It has the chemical symbol Ca. It is one of the commonest metals in the Earth’s crust. It reacts easily with many other elements, and...
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When Does Coal Become a Precious Stone?
Coal is basically a compound consisting largely of carbon. When a piece of carbon deep underground is subjected to great heat and pressure, it may gradually be...
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When Do Bones Break?
When Do Bones Break? Bones break under varying degrees of pressure according to age, health and other circumstances. They are made of hard, strong connective tissue and...
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